A known electrowetting display apparatus comprises first and second immiscible fluids between first and second support plates. The first support plate has a plurality of display areas for forming images thereon each display area confining a portion of the first fluid. This can be done by forming each display area as a first surface, less wettable to the second fluid than a second surface which forms a boundary to the first surface. The first surface has a layer of the first fluid upon it when the device is not in operation, the first fluid being constrained in the display area by the second surface. The first fluid is electrically non-conductive and may for instance be an alkane like hexadecane, or silicone oil. The second fluid is electrically conductive or polar, and may be water or a salt solution such as a solution of potassium chloride in a mixture of water and ethyl alcohol.
An electrode is positioned below the display area and when a voltage is applied between this electrode and the second fluid, the second fluid is attracted to the first surface. Accordingly, the first fluid is displaced. The configuration of the first and second fluid can therefore be controlled to provide a display effect in the display area.
It is desirable to provide an improved electrowetting display.
Several parts and components appear in more than one Figure; for the sake of clarity the same reference numeral will be used to refer to the same part and component in all of the Figures.